Respuesta :

Question 7:

Diameter = 6.2 cm so Radius = 3.1 cm
A=πr² = 3.14 × 3.1² = 30.1754 cm² = 30.18 cm²

Question 8:

Circumference = 2πr
16π = 2πr
therefore 16 = 2r so r = 8cm 
7. Area is diameter times pi so 6.2 x 3.14 = 19.468 so your answer is B.
8. Because the circumference is 16 pi all you have to do is divide 16 by 2 so your answer is C.
Hope this helps!